02476nas a2200277   4500008004600000245014300046210006900189300001600258490000800274520150900282653002201791653003201813653002401845653001201869653002301881653002801904653003601932653002201968653005401990653002002044653000902064653003602073100001702109700002202126856005002148       Submitted                   eng d     00ap38 MAPK is a likely component of the signal transduction pathway triggering rapid cold hardening in the flesh fly Sarcophaga crassipalpis0 ap38 MAPK is a likely component of the signal transduction pathwa  a3295 - 33000 v2103 aRapid cold hardening (RCH) is an adaptation enabling insects to quickly respond to low temperature, but little is known about the molecular events that trigger this response. In this study of the flesh fly Sarcophaga crassipalpis, we explore a possible role for mitogen-activated protein kinases (MAPKs) in the low temperature signaling that elicits RCH. We report that p38 MAPK from S. crassipalpis, which shows high cDNA sequence homology to p38 MAPKs from other insects and mammals, is rapidly activated at temperatures around 0 degrees C, temperatures that are most effective for inducing RCH. By contrast, low temperature does not activate either extracellular signal-regulated kinase (ERK) or Jun N-terminal kinase (JNK). An increase in phospho-p38 MAPK was observed within 10 min following exposure to 0 degrees C and reached its maximum level in 2 h. When flies were transferred from 0 to 25 degrees C, the level of phospho-p38 MAPK decreased immediately and reached trace levels by 3 h. Nondiapausing flies were much more responsive to p38 MAPK activation than cold-hardy diapausing pupae. Thus, p38 MAPK activation and RCH both show the same narrow ranges of temperature sensitivity, temporal profiles of activation and decay, and developmental specificity. These correlations suggest that p38 MAPK plays a potential role in regulating the induction of RCH. The p38 MAPK response was not dependent upon the brain, as evidenced by high activation in isolated abdomens exposed to low temperature.10a*Cold Temperature10aAcclimatization/*physiology10aAmino Acid Sequence10aAnimals10aCloning, Molecular10adevelopment/*physiology10aDiptera/*enzymology/growth &amp10aEnzyme Activation10ap38 Mitogen-Activated Protein Kinases/*metabolism10aPhosphorylation10aPupa10aSignal Transduction/*physiology1 aFujiwara, Y.1 aDenlinger, D., L.  uhttps://sarcophagidae.myspecies.info/node/47002663nas a2200265   4500008004600000245011800046210006900164300001400233490000700247520177500254653002402029653001202053653003002065653002802095653003402123653004202157653003002199653002002229653002802249100002002277700001502297700001802312700001702330856005002347       Submitted                   eng d     00aBiphasic metabolic rate trajectory of pupal diapause termination and post-diapause development in a tephritid fly0 aBiphasic metabolic rate trajectory of pupal diapause termination  a344 - 3500 v553 aMetabolic depression is a highly conserved feature of insect diapause, and an increase in metabolism is a reliable indicator of diapause termination and the initiation of post-diapause development. The trajectory of metabolic rate following diapause termination can guide the identification of important physiological and developmental landmarks during this developmental transition, yet quantitative descriptions of these trajectories are relatively rare. Here we track changes in metabolic rate from diapause through diapause termination and pharate adult development in Rhagoletis pomonella (Diptera: Tephritidae), a univoltine tephritid fly that diapauses in the pupal stage. Using respirometric monitoring we show that diapause termination and subsequent pharate adult development is characterized by a biphasic increase in metabolic rate. Respiration rate initially increases logistically, reaching a plateau that is followed by a final, exponential increase terminating in adult eclosion. We develop a non-linear model describing this pattern with easily interpretable landmarks, and we map visible landmarks of morphogenesis onto the trajectory. The bulk of visible morphogenesis in pharate adult development occurs relatively late in the trajectory during the final, exponential phase, that matches the U-shaped trajectory of non-diapause individuals. These results mirror a qualitative description of the same trajectories of diapause and non-diapause flesh flies (Sarcophaga). Overall, our results suggest that (1) the course of diapause breakage and post-diapause development may be evolutionarily conserved in higher flies with pupal diapause, and (2) the biphasic trajectory is distinct from a more continuous trajectory observed during direct development.10a*Models, Biological10aAnimals10aCarbon Dioxide/metabolism10adevelopment/*physiology10aEnergy Metabolism/*physiology10aMetamorphosis, Biological/*physiology10aMorphogenesis/*physiology10aPupa/physiology10aTephritidae/growth &amp1 aRagland, G., J.1 aFuller, J.1 aFeder, J., L.1 aHahn, D., A.  uhttps://sarcophagidae.myspecies.info/node/287